Organ
Cervix
The uterine neck surrounding the cervical canal
High-yield
The ectocervix usually has stratified squamous epithelium; the endocervical canal has mucus-secreting columnar epithelium. Metaplasia around their changing junction forms the transformation zone.
Overview
The cervix connects the uterine body with the vagina. Its collagen-rich wall surrounds a canal between the internal and external openings, and its lower portion projects into the vaginal vault. The surrounding fornices reflect the vagina's attachment to the cervical wall.
Reference facts
- Location
- Between the uterine isthmus and vagina, with supravaginal and vaginal portions.
- Parts
- A cervical canal connects internal and external os; the vaginal portion is surrounded by anterior, posterior and lateral fornices.
- Blood supply
- Cervical branches of the uterine artery communicate with vaginal arterial branches.
- Innervation
- The uterovaginal plexus carries autonomic and sensory fibers. Both thoracolumbar and sacral sensory connections exist; first-stage labor pain is principally associated with T10–L1.
- Venous/Lymphatic drainage
- Venous blood joins uterine and vaginal plexuses; lymph has iliac, obturator and sacral connections.
- Relations
- Related anteriorly to the bladder, posteriorly to the rectouterine region, and laterally to paracervical tissues containing vessels near the ureter.
- Function
- Produces cycle-dependent mucus, helps protect the uterine cavity and undergoes remodelling and dilatation during childbirth.
Clinical correlation
Cervical dilatation contributes to first-stage labor pain carried mainly to T10–L1; later perineal distension adds sacral somatic input. The adjacent uterine artery and ureter are important pelvic surgical relations. Nabothian cysts arise when cervical gland outlets become covered.
Frequently asked questions
Where is the cervix located?
Between the uterine isthmus and vagina, with supravaginal and vaginal portions.
What does the cervix do?
Produces cycle-dependent mucus, helps protect the uterine cavity and undergoes remodelling and dilatation during childbirth.
What are the parts of the cervix?
A cervical canal connects internal and external os; the vaginal portion is surrounded by anterior, posterior and lateral fornices.
What is the blood supply of the cervix?
The cervix is supplied by the cervical branches of the uterine artery communicate with vaginal arterial branches.